Too tired to party
Here we have another case of sharing your time as a parent between your children. In this situation, having 3 children who’s birthdays are so close together must make things like this a little tricky. However, it doesn’t sound as if his children are older, so he’s had time to work it all out.
Making the effort for your son, but then deciding you’re too tired to see your daughters, is out of order, though. I agree with his wife in it being an unacceptable attitude. His daughters must have felt so hurt and a little abandoned. He’s going to have to make it up to them soon.